How Do You Calculate Tension in a Hanging Mirror?

AI Thread Summary
To calculate the tension in a hanging mirror, the vertical components of the tension forces must be considered, leading to the equation 2TSin(45) = mg, where m is the mass of the mirror. The factor of 2 arises from the two strings supporting the mirror. Each string contributes an upward force of T/√2, balancing the weight of the mirror. Modifying the setup to connect the strings in parallel allows for increased maximum force capacity due to the distribution of tension across multiple strings. Understanding these principles is crucial for solving equilibrium problems involving hanging objects.
Arabell
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Homework Statement



Diagram 4 shows a 2 kg mirror hung on a wall using strings of the same length . The mirror is in equilibrium state.

a) On Diagram 4 , label the force that act on the mirror .

b) Calculate the tension of the string , T that act on the mirror .

c) Suggest a modification to be made so that the string can withstand a larger maximum force .

Homework Equations

The Attempt at a Solution



I had only drawn a free body diagram and I am already stuck and don't know what to do... Help me please , any solution to this question would be greatly aprreciated .
 

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Solution

First we must take the vertical component of the tension forces acting on the mirror. Let the mass of mirror be m
Then
2TSin45=mg
solve for T by substituting the values.
A modification which can be made is connecting the strings parallely
 
FermionXLR8r said:
First we must take the vertical component of the tension forces acting on the mirror. Let the mass of mirror be m
Then
2TSin45=mg
solve for T by substituting the values.
A modification which can be made is

Thanks mate for replying ... In the equation , where does 2 come from , does it come from the mirror which is 2 kg since it is an equilibrium state . Another thing is can you explain why connecting the strings parallely enables it to withstand a larger maximum force
 
Arabell said:
where does 2 come from , does it come from the mirror which is 2 kg since it is an equilibrium state . Another thing is can you explain why connecting the strings parallely enables it to withstand a larger maximum force
The 2 is because there are two strings. If the tension is T, each each string is supplying an upwards force of T sin (45) = T/√2. Since that balances the weight of the mirror, what is T?

If the strings were vertical with tension U, what would the equation be?
 
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